Configuration of the S-alkyl thiohydroximates: crystal-structure analysis of the syn-(alkylthio)-isomer of S-cyanoethyl acetothiohydroximate

Abstract

The syn-(alkylthio)-configuration of the thermodynamically more stable α-isomer of S-cyanoethyl acetothio-hydroximate has been confirmed by crystal-structure determination. The compound crystallizes in the monoclinic space group P2₁/c, with a= 16·535 ± 0·011, b= 4·654 ± 0·003, c= 19·536 ± 0·012 Å, β= 106° 44′± 2′, and Z= 8. The X-ray intensities were measured on a computer-controlled four-circle diffractometer with Mo-K_α radiation. The atomic co-ordinates were determined by Fourier and least-squares methods to give R 0·069 over 903 independent reflections. The CN, CN, N–O, C(sp)–C(sp³), C(sp²)–C(sp³), C(sp³)–C(sp³), S–C(sp²), and S–C(sp³) bonds have lengths of 1·28, 1·13, 1·41, 1·45, 1·50, 1·52, 1·76, and 1·82 Å, respectively, with standard deviations of ca. 0·01 Å.